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<pre><span class="sourceLineNo">001</span>/*<a name="line.1"></a>
<span class="sourceLineNo">002</span> * Copyright (C) 2007 The Guava Authors<a name="line.2"></a>
<span class="sourceLineNo">003</span> *<a name="line.3"></a>
<span class="sourceLineNo">004</span> * Licensed under the Apache License, Version 2.0 (the "License");<a name="line.4"></a>
<span class="sourceLineNo">005</span> * you may not use this file except in compliance with the License.<a name="line.5"></a>
<span class="sourceLineNo">006</span> * You may obtain a copy of the License at<a name="line.6"></a>
<span class="sourceLineNo">007</span> *<a name="line.7"></a>
<span class="sourceLineNo">008</span> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.8"></a>
<span class="sourceLineNo">009</span> *<a name="line.9"></a>
<span class="sourceLineNo">010</span> * Unless required by applicable law or agreed to in writing, software<a name="line.10"></a>
<span class="sourceLineNo">011</span> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.11"></a>
<span class="sourceLineNo">012</span> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.12"></a>
<span class="sourceLineNo">013</span> * See the License for the specific language governing permissions and<a name="line.13"></a>
<span class="sourceLineNo">014</span> * limitations under the License.<a name="line.14"></a>
<span class="sourceLineNo">015</span> */<a name="line.15"></a>
<span class="sourceLineNo">016</span><a name="line.16"></a>
<span class="sourceLineNo">017</span>package com.google.common.collect;<a name="line.17"></a>
<span class="sourceLineNo">018</span><a name="line.18"></a>
<span class="sourceLineNo">019</span>import static com.google.common.base.Preconditions.checkArgument;<a name="line.19"></a>
<span class="sourceLineNo">020</span>import static com.google.common.base.Preconditions.checkNotNull;<a name="line.20"></a>
<span class="sourceLineNo">021</span><a name="line.21"></a>
<span class="sourceLineNo">022</span>import com.google.common.annotations.Beta;<a name="line.22"></a>
<span class="sourceLineNo">023</span>import com.google.common.annotations.GwtCompatible;<a name="line.23"></a>
<span class="sourceLineNo">024</span>import com.google.common.annotations.GwtIncompatible;<a name="line.24"></a>
<span class="sourceLineNo">025</span>import com.google.common.base.Function;<a name="line.25"></a>
<span class="sourceLineNo">026</span>import com.google.common.base.Optional;<a name="line.26"></a>
<span class="sourceLineNo">027</span>import com.google.common.base.Preconditions;<a name="line.27"></a>
<span class="sourceLineNo">028</span>import com.google.common.base.Predicate;<a name="line.28"></a>
<span class="sourceLineNo">029</span><a name="line.29"></a>
<span class="sourceLineNo">030</span>import java.util.Arrays;<a name="line.30"></a>
<span class="sourceLineNo">031</span>import java.util.Collection;<a name="line.31"></a>
<span class="sourceLineNo">032</span>import java.util.Collections;<a name="line.32"></a>
<span class="sourceLineNo">033</span>import java.util.Comparator;<a name="line.33"></a>
<span class="sourceLineNo">034</span>import java.util.Iterator;<a name="line.34"></a>
<span class="sourceLineNo">035</span>import java.util.List;<a name="line.35"></a>
<span class="sourceLineNo">036</span>import java.util.NoSuchElementException;<a name="line.36"></a>
<span class="sourceLineNo">037</span>import java.util.Queue;<a name="line.37"></a>
<span class="sourceLineNo">038</span>import java.util.RandomAccess;<a name="line.38"></a>
<span class="sourceLineNo">039</span>import java.util.Set;<a name="line.39"></a>
<span class="sourceLineNo">040</span>import java.util.SortedSet;<a name="line.40"></a>
<span class="sourceLineNo">041</span><a name="line.41"></a>
<span class="sourceLineNo">042</span>import javax.annotation.Nullable;<a name="line.42"></a>
<span class="sourceLineNo">043</span><a name="line.43"></a>
<span class="sourceLineNo">044</span>/**<a name="line.44"></a>
<span class="sourceLineNo">045</span> * This class contains static utility methods that operate on or return objects<a name="line.45"></a>
<span class="sourceLineNo">046</span> * of type {@code Iterable}. Except as noted, each method has a corresponding<a name="line.46"></a>
<span class="sourceLineNo">047</span> * {@link Iterator}-based method in the {@link Iterators} class.<a name="line.47"></a>
<span class="sourceLineNo">048</span> *<a name="line.48"></a>
<span class="sourceLineNo">049</span> * &lt;p&gt;&lt;i&gt;Performance notes:&lt;/i&gt; Unless otherwise noted, all of the iterables<a name="line.49"></a>
<span class="sourceLineNo">050</span> * produced in this class are &lt;i&gt;lazy&lt;/i&gt;, which means that their iterators<a name="line.50"></a>
<span class="sourceLineNo">051</span> * only advance the backing iteration when absolutely necessary.<a name="line.51"></a>
<span class="sourceLineNo">052</span> *<a name="line.52"></a>
<span class="sourceLineNo">053</span> * &lt;p&gt;See the Guava User Guide article on &lt;a href=<a name="line.53"></a>
<span class="sourceLineNo">054</span> * "http://code.google.com/p/guava-libraries/wiki/CollectionUtilitiesExplained#Iterables"&gt;<a name="line.54"></a>
<span class="sourceLineNo">055</span> * {@code Iterables}&lt;/a&gt;.<a name="line.55"></a>
<span class="sourceLineNo">056</span> *<a name="line.56"></a>
<span class="sourceLineNo">057</span> * @author Kevin Bourrillion<a name="line.57"></a>
<span class="sourceLineNo">058</span> * @author Jared Levy<a name="line.58"></a>
<span class="sourceLineNo">059</span> * @since 2.0 (imported from Google Collections Library)<a name="line.59"></a>
<span class="sourceLineNo">060</span> */<a name="line.60"></a>
<span class="sourceLineNo">061</span>@GwtCompatible(emulated = true)<a name="line.61"></a>
<span class="sourceLineNo">062</span>public final class Iterables {<a name="line.62"></a>
<span class="sourceLineNo">063</span>  private Iterables() {}<a name="line.63"></a>
<span class="sourceLineNo">064</span><a name="line.64"></a>
<span class="sourceLineNo">065</span>  /** Returns an unmodifiable view of {@code iterable}. */<a name="line.65"></a>
<span class="sourceLineNo">066</span>  public static &lt;T&gt; Iterable&lt;T&gt; unmodifiableIterable(<a name="line.66"></a>
<span class="sourceLineNo">067</span>      final Iterable&lt;T&gt; iterable) {<a name="line.67"></a>
<span class="sourceLineNo">068</span>    checkNotNull(iterable);<a name="line.68"></a>
<span class="sourceLineNo">069</span>    if (iterable instanceof UnmodifiableIterable ||<a name="line.69"></a>
<span class="sourceLineNo">070</span>        iterable instanceof ImmutableCollection) {<a name="line.70"></a>
<span class="sourceLineNo">071</span>      return iterable;<a name="line.71"></a>
<span class="sourceLineNo">072</span>    }<a name="line.72"></a>
<span class="sourceLineNo">073</span>    return new UnmodifiableIterable&lt;T&gt;(iterable);<a name="line.73"></a>
<span class="sourceLineNo">074</span>  }<a name="line.74"></a>
<span class="sourceLineNo">075</span><a name="line.75"></a>
<span class="sourceLineNo">076</span>  /**<a name="line.76"></a>
<span class="sourceLineNo">077</span>   * Simply returns its argument.<a name="line.77"></a>
<span class="sourceLineNo">078</span>   *<a name="line.78"></a>
<span class="sourceLineNo">079</span>   * @deprecated no need to use this<a name="line.79"></a>
<span class="sourceLineNo">080</span>   * @since 10.0<a name="line.80"></a>
<span class="sourceLineNo">081</span>   */<a name="line.81"></a>
<span class="sourceLineNo">082</span>  @Deprecated public static &lt;E&gt; Iterable&lt;E&gt; unmodifiableIterable(<a name="line.82"></a>
<span class="sourceLineNo">083</span>      ImmutableCollection&lt;E&gt; iterable) {<a name="line.83"></a>
<span class="sourceLineNo">084</span>    return checkNotNull(iterable);<a name="line.84"></a>
<span class="sourceLineNo">085</span>  }<a name="line.85"></a>
<span class="sourceLineNo">086</span><a name="line.86"></a>
<span class="sourceLineNo">087</span>  private static final class UnmodifiableIterable&lt;T&gt; extends FluentIterable&lt;T&gt; {<a name="line.87"></a>
<span class="sourceLineNo">088</span>    private final Iterable&lt;T&gt; iterable;<a name="line.88"></a>
<span class="sourceLineNo">089</span><a name="line.89"></a>
<span class="sourceLineNo">090</span>    private UnmodifiableIterable(Iterable&lt;T&gt; iterable) {<a name="line.90"></a>
<span class="sourceLineNo">091</span>      this.iterable = iterable;<a name="line.91"></a>
<span class="sourceLineNo">092</span>    }<a name="line.92"></a>
<span class="sourceLineNo">093</span><a name="line.93"></a>
<span class="sourceLineNo">094</span>    @Override<a name="line.94"></a>
<span class="sourceLineNo">095</span>    public Iterator&lt;T&gt; iterator() {<a name="line.95"></a>
<span class="sourceLineNo">096</span>      return Iterators.unmodifiableIterator(iterable.iterator());<a name="line.96"></a>
<span class="sourceLineNo">097</span>    }<a name="line.97"></a>
<span class="sourceLineNo">098</span><a name="line.98"></a>
<span class="sourceLineNo">099</span>    @Override<a name="line.99"></a>
<span class="sourceLineNo">100</span>    public String toString() {<a name="line.100"></a>
<span class="sourceLineNo">101</span>      return iterable.toString();<a name="line.101"></a>
<span class="sourceLineNo">102</span>    }<a name="line.102"></a>
<span class="sourceLineNo">103</span>    // no equals and hashCode; it would break the contract!<a name="line.103"></a>
<span class="sourceLineNo">104</span>  }<a name="line.104"></a>
<span class="sourceLineNo">105</span><a name="line.105"></a>
<span class="sourceLineNo">106</span>  /**<a name="line.106"></a>
<span class="sourceLineNo">107</span>   * Returns the number of elements in {@code iterable}.<a name="line.107"></a>
<span class="sourceLineNo">108</span>   */<a name="line.108"></a>
<span class="sourceLineNo">109</span>  public static int size(Iterable&lt;?&gt; iterable) {<a name="line.109"></a>
<span class="sourceLineNo">110</span>    return (iterable instanceof Collection)<a name="line.110"></a>
<span class="sourceLineNo">111</span>        ? ((Collection&lt;?&gt;) iterable).size()<a name="line.111"></a>
<span class="sourceLineNo">112</span>        : Iterators.size(iterable.iterator());<a name="line.112"></a>
<span class="sourceLineNo">113</span>  }<a name="line.113"></a>
<span class="sourceLineNo">114</span><a name="line.114"></a>
<span class="sourceLineNo">115</span>  /**<a name="line.115"></a>
<span class="sourceLineNo">116</span>   * Returns {@code true} if {@code iterable} contains any object for which {@code equals(element)}<a name="line.116"></a>
<span class="sourceLineNo">117</span>   * is true.<a name="line.117"></a>
<span class="sourceLineNo">118</span>   */<a name="line.118"></a>
<span class="sourceLineNo">119</span>  public static boolean contains(Iterable&lt;?&gt; iterable, @Nullable Object element)<a name="line.119"></a>
<span class="sourceLineNo">120</span>  {<a name="line.120"></a>
<span class="sourceLineNo">121</span>    if (iterable instanceof Collection) {<a name="line.121"></a>
<span class="sourceLineNo">122</span>      Collection&lt;?&gt; collection = (Collection&lt;?&gt;) iterable;<a name="line.122"></a>
<span class="sourceLineNo">123</span>      try {<a name="line.123"></a>
<span class="sourceLineNo">124</span>        return collection.contains(element);<a name="line.124"></a>
<span class="sourceLineNo">125</span>      } catch (NullPointerException e) {<a name="line.125"></a>
<span class="sourceLineNo">126</span>        return false;<a name="line.126"></a>
<span class="sourceLineNo">127</span>      } catch (ClassCastException e) {<a name="line.127"></a>
<span class="sourceLineNo">128</span>        return false;<a name="line.128"></a>
<span class="sourceLineNo">129</span>      }<a name="line.129"></a>
<span class="sourceLineNo">130</span>    }<a name="line.130"></a>
<span class="sourceLineNo">131</span>    return Iterators.contains(iterable.iterator(), element);<a name="line.131"></a>
<span class="sourceLineNo">132</span>  }<a name="line.132"></a>
<span class="sourceLineNo">133</span><a name="line.133"></a>
<span class="sourceLineNo">134</span>  /**<a name="line.134"></a>
<span class="sourceLineNo">135</span>   * Removes, from an iterable, every element that belongs to the provided<a name="line.135"></a>
<span class="sourceLineNo">136</span>   * collection.<a name="line.136"></a>
<span class="sourceLineNo">137</span>   *<a name="line.137"></a>
<span class="sourceLineNo">138</span>   * &lt;p&gt;This method calls {@link Collection#removeAll} if {@code iterable} is a<a name="line.138"></a>
<span class="sourceLineNo">139</span>   * collection, and {@link Iterators#removeAll} otherwise.<a name="line.139"></a>
<span class="sourceLineNo">140</span>   *<a name="line.140"></a>
<span class="sourceLineNo">141</span>   * @param removeFrom the iterable to (potentially) remove elements from<a name="line.141"></a>
<span class="sourceLineNo">142</span>   * @param elementsToRemove the elements to remove<a name="line.142"></a>
<span class="sourceLineNo">143</span>   * @return {@code true} if any element was removed from {@code iterable}<a name="line.143"></a>
<span class="sourceLineNo">144</span>   */<a name="line.144"></a>
<span class="sourceLineNo">145</span>  public static boolean removeAll(<a name="line.145"></a>
<span class="sourceLineNo">146</span>      Iterable&lt;?&gt; removeFrom, Collection&lt;?&gt; elementsToRemove) {<a name="line.146"></a>
<span class="sourceLineNo">147</span>    return (removeFrom instanceof Collection)<a name="line.147"></a>
<span class="sourceLineNo">148</span>        ? ((Collection&lt;?&gt;) removeFrom).removeAll(checkNotNull(elementsToRemove))<a name="line.148"></a>
<span class="sourceLineNo">149</span>        : Iterators.removeAll(removeFrom.iterator(), elementsToRemove);<a name="line.149"></a>
<span class="sourceLineNo">150</span>  }<a name="line.150"></a>
<span class="sourceLineNo">151</span><a name="line.151"></a>
<span class="sourceLineNo">152</span>  /**<a name="line.152"></a>
<span class="sourceLineNo">153</span>   * Removes, from an iterable, every element that does not belong to the<a name="line.153"></a>
<span class="sourceLineNo">154</span>   * provided collection.<a name="line.154"></a>
<span class="sourceLineNo">155</span>   *<a name="line.155"></a>
<span class="sourceLineNo">156</span>   * &lt;p&gt;This method calls {@link Collection#retainAll} if {@code iterable} is a<a name="line.156"></a>
<span class="sourceLineNo">157</span>   * collection, and {@link Iterators#retainAll} otherwise.<a name="line.157"></a>
<span class="sourceLineNo">158</span>   *<a name="line.158"></a>
<span class="sourceLineNo">159</span>   * @param removeFrom the iterable to (potentially) remove elements from<a name="line.159"></a>
<span class="sourceLineNo">160</span>   * @param elementsToRetain the elements to retain<a name="line.160"></a>
<span class="sourceLineNo">161</span>   * @return {@code true} if any element was removed from {@code iterable}<a name="line.161"></a>
<span class="sourceLineNo">162</span>   */<a name="line.162"></a>
<span class="sourceLineNo">163</span>  public static boolean retainAll(<a name="line.163"></a>
<span class="sourceLineNo">164</span>      Iterable&lt;?&gt; removeFrom, Collection&lt;?&gt; elementsToRetain) {<a name="line.164"></a>
<span class="sourceLineNo">165</span>    return (removeFrom instanceof Collection)<a name="line.165"></a>
<span class="sourceLineNo">166</span>        ? ((Collection&lt;?&gt;) removeFrom).retainAll(checkNotNull(elementsToRetain))<a name="line.166"></a>
<span class="sourceLineNo">167</span>        : Iterators.retainAll(removeFrom.iterator(), elementsToRetain);<a name="line.167"></a>
<span class="sourceLineNo">168</span>  }<a name="line.168"></a>
<span class="sourceLineNo">169</span><a name="line.169"></a>
<span class="sourceLineNo">170</span>  /**<a name="line.170"></a>
<span class="sourceLineNo">171</span>   * Removes, from an iterable, every element that satisfies the provided<a name="line.171"></a>
<span class="sourceLineNo">172</span>   * predicate.<a name="line.172"></a>
<span class="sourceLineNo">173</span>   *<a name="line.173"></a>
<span class="sourceLineNo">174</span>   * @param removeFrom the iterable to (potentially) remove elements from<a name="line.174"></a>
<span class="sourceLineNo">175</span>   * @param predicate a predicate that determines whether an element should<a name="line.175"></a>
<span class="sourceLineNo">176</span>   *     be removed<a name="line.176"></a>
<span class="sourceLineNo">177</span>   * @return {@code true} if any elements were removed from the iterable<a name="line.177"></a>
<span class="sourceLineNo">178</span>   *<a name="line.178"></a>
<span class="sourceLineNo">179</span>   * @throws UnsupportedOperationException if the iterable does not support<a name="line.179"></a>
<span class="sourceLineNo">180</span>   *     {@code remove()}.<a name="line.180"></a>
<span class="sourceLineNo">181</span>   * @since 2.0<a name="line.181"></a>
<span class="sourceLineNo">182</span>   */<a name="line.182"></a>
<span class="sourceLineNo">183</span>  public static &lt;T&gt; boolean removeIf(<a name="line.183"></a>
<span class="sourceLineNo">184</span>      Iterable&lt;T&gt; removeFrom, Predicate&lt;? super T&gt; predicate) {<a name="line.184"></a>
<span class="sourceLineNo">185</span>    if (removeFrom instanceof RandomAccess &amp;&amp; removeFrom instanceof List) {<a name="line.185"></a>
<span class="sourceLineNo">186</span>      return removeIfFromRandomAccessList(<a name="line.186"></a>
<span class="sourceLineNo">187</span>          (List&lt;T&gt;) removeFrom, checkNotNull(predicate));<a name="line.187"></a>
<span class="sourceLineNo">188</span>    }<a name="line.188"></a>
<span class="sourceLineNo">189</span>    return Iterators.removeIf(removeFrom.iterator(), predicate);<a name="line.189"></a>
<span class="sourceLineNo">190</span>  }<a name="line.190"></a>
<span class="sourceLineNo">191</span><a name="line.191"></a>
<span class="sourceLineNo">192</span>  private static &lt;T&gt; boolean removeIfFromRandomAccessList(<a name="line.192"></a>
<span class="sourceLineNo">193</span>      List&lt;T&gt; list, Predicate&lt;? super T&gt; predicate) {<a name="line.193"></a>
<span class="sourceLineNo">194</span>    // Note: Not all random access lists support set() so we need to deal with<a name="line.194"></a>
<span class="sourceLineNo">195</span>    // those that don't and attempt the slower remove() based solution.<a name="line.195"></a>
<span class="sourceLineNo">196</span>    int from = 0;<a name="line.196"></a>
<span class="sourceLineNo">197</span>    int to = 0;<a name="line.197"></a>
<span class="sourceLineNo">198</span><a name="line.198"></a>
<span class="sourceLineNo">199</span>    for (; from &lt; list.size(); from++) {<a name="line.199"></a>
<span class="sourceLineNo">200</span>      T element = list.get(from);<a name="line.200"></a>
<span class="sourceLineNo">201</span>      if (!predicate.apply(element)) {<a name="line.201"></a>
<span class="sourceLineNo">202</span>        if (from &gt; to) {<a name="line.202"></a>
<span class="sourceLineNo">203</span>          try {<a name="line.203"></a>
<span class="sourceLineNo">204</span>            list.set(to, element);<a name="line.204"></a>
<span class="sourceLineNo">205</span>          } catch (UnsupportedOperationException e) {<a name="line.205"></a>
<span class="sourceLineNo">206</span>            slowRemoveIfForRemainingElements(list, predicate, to, from);<a name="line.206"></a>
<span class="sourceLineNo">207</span>            return true;<a name="line.207"></a>
<span class="sourceLineNo">208</span>          }<a name="line.208"></a>
<span class="sourceLineNo">209</span>        }<a name="line.209"></a>
<span class="sourceLineNo">210</span>        to++;<a name="line.210"></a>
<span class="sourceLineNo">211</span>      }<a name="line.211"></a>
<span class="sourceLineNo">212</span>    }<a name="line.212"></a>
<span class="sourceLineNo">213</span><a name="line.213"></a>
<span class="sourceLineNo">214</span>    // Clear the tail of any remaining items<a name="line.214"></a>
<span class="sourceLineNo">215</span>    list.subList(to, list.size()).clear();<a name="line.215"></a>
<span class="sourceLineNo">216</span>    return from != to;<a name="line.216"></a>
<span class="sourceLineNo">217</span>  }<a name="line.217"></a>
<span class="sourceLineNo">218</span><a name="line.218"></a>
<span class="sourceLineNo">219</span>  private static &lt;T&gt; void slowRemoveIfForRemainingElements(List&lt;T&gt; list,<a name="line.219"></a>
<span class="sourceLineNo">220</span>      Predicate&lt;? super T&gt; predicate, int to, int from) {<a name="line.220"></a>
<span class="sourceLineNo">221</span>    // Here we know that:<a name="line.221"></a>
<span class="sourceLineNo">222</span>    // * (to &lt; from) and that both are valid indices.<a name="line.222"></a>
<span class="sourceLineNo">223</span>    // * Everything with (index &lt; to) should be kept.<a name="line.223"></a>
<span class="sourceLineNo">224</span>    // * Everything with (to &lt;= index &lt; from) should be removed.<a name="line.224"></a>
<span class="sourceLineNo">225</span>    // * The element with (index == from) should be kept.<a name="line.225"></a>
<span class="sourceLineNo">226</span>    // * Everything with (index &gt; from) has not been checked yet.<a name="line.226"></a>
<span class="sourceLineNo">227</span><a name="line.227"></a>
<span class="sourceLineNo">228</span>    // Check from the end of the list backwards (minimize expected cost of<a name="line.228"></a>
<span class="sourceLineNo">229</span>    // moving elements when remove() is called). Stop before 'from' because<a name="line.229"></a>
<span class="sourceLineNo">230</span>    // we already know that should be kept.<a name="line.230"></a>
<span class="sourceLineNo">231</span>    for (int n = list.size() - 1; n &gt; from; n--) {<a name="line.231"></a>
<span class="sourceLineNo">232</span>      if (predicate.apply(list.get(n))) {<a name="line.232"></a>
<span class="sourceLineNo">233</span>        list.remove(n);<a name="line.233"></a>
<span class="sourceLineNo">234</span>      }<a name="line.234"></a>
<span class="sourceLineNo">235</span>    }<a name="line.235"></a>
<span class="sourceLineNo">236</span>    // And now remove everything in the range [to, from) (going backwards).<a name="line.236"></a>
<span class="sourceLineNo">237</span>    for (int n = from - 1; n &gt;= to; n--) {<a name="line.237"></a>
<span class="sourceLineNo">238</span>      list.remove(n);<a name="line.238"></a>
<span class="sourceLineNo">239</span>    }<a name="line.239"></a>
<span class="sourceLineNo">240</span>  }<a name="line.240"></a>
<span class="sourceLineNo">241</span><a name="line.241"></a>
<span class="sourceLineNo">242</span>  /**<a name="line.242"></a>
<span class="sourceLineNo">243</span>   * Determines whether two iterables contain equal elements in the same order.<a name="line.243"></a>
<span class="sourceLineNo">244</span>   * More specifically, this method returns {@code true} if {@code iterable1}<a name="line.244"></a>
<span class="sourceLineNo">245</span>   * and {@code iterable2} contain the same number of elements and every element<a name="line.245"></a>
<span class="sourceLineNo">246</span>   * of {@code iterable1} is equal to the corresponding element of<a name="line.246"></a>
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<span class="sourceLineNo">255</span>   * Returns a string representation of {@code iterable}, with the format<a name="line.255"></a>
<span class="sourceLineNo">256</span>   * {@code [e1, e2, ..., en]}.<a name="line.256"></a>
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<span class="sourceLineNo">302</span>   * Copies an iterable's elements into an array.<a name="line.302"></a>
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<span class="sourceLineNo">340</span>   * specified object. This implementation avoids a full iteration when the<a name="line.340"></a>
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<span class="sourceLineNo">364</span>   *<a name="line.364"></a>
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<span class="sourceLineNo">366</span>   * infinite loop. You should use an explicit {@code break} or be certain that<a name="line.366"></a>
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<span class="sourceLineNo">368</span>   *<a name="line.368"></a>
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<span class="sourceLineNo">387</span>   * elements.<a name="line.387"></a>
<span class="sourceLineNo">388</span>   *<a name="line.388"></a>
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<span class="sourceLineNo">390</span>   * element will no longer appear in either that iterator or any other iterator<a name="line.390"></a>
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<span class="sourceLineNo">395</span>   *<a name="line.395"></a>
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<span class="sourceLineNo">399</span>   *<a name="line.399"></a>
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<span class="sourceLineNo">409</span>   * iterator that traverses the elements in {@code a}, followed by the elements<a name="line.409"></a>
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<span class="sourceLineNo">411</span>   *<a name="line.411"></a>
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<span class="sourceLineNo">425</span>   * an iterator that traverses the elements in {@code a}, followed by the<a name="line.425"></a>
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<span class="sourceLineNo">428</span>   *<a name="line.428"></a>
<span class="sourceLineNo">429</span>   * &lt;p&gt;The returned iterable's iterator supports {@code remove()} when the<a name="line.429"></a>
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<span class="sourceLineNo">447</span>   *<a name="line.447"></a>
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<span class="sourceLineNo">456</span>    checkNotNull(b);<a name="line.456"></a>
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<span class="sourceLineNo">464</span>   * has an iterator that traverses the elements of each iterable in<a name="line.464"></a>
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<span class="sourceLineNo">466</span>   *<a name="line.466"></a>
<span class="sourceLineNo">467</span>   * &lt;p&gt;The returned iterable's iterator supports {@code remove()} when the<a name="line.467"></a>
<span class="sourceLineNo">468</span>   * corresponding input iterator supports it.<a name="line.468"></a>
<span class="sourceLineNo">469</span>   *<a name="line.469"></a>
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<span class="sourceLineNo">594</span>   * Returns all instances of class {@code type} in {@code unfiltered}. The<a name="line.594"></a>
<span class="sourceLineNo">595</span>   * returned iterable has elements whose class is {@code type} or a subclass of<a name="line.595"></a>
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<span class="sourceLineNo">665</span>   *<a name="line.665"></a>
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<span class="sourceLineNo">668</span>   * NullPointerException will be thrown.<a name="line.668"></a>
<span class="sourceLineNo">669</span>   *<a name="line.669"></a>
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<span class="sourceLineNo">680</span>   * elements.<a name="line.680"></a>
<span class="sourceLineNo">681</span>   *<a name="line.681"></a>
<span class="sourceLineNo">682</span>   * &lt;p&gt;More formally, returns the lowest index {@code i} such that<a name="line.682"></a>
<span class="sourceLineNo">683</span>   * {@code predicate.apply(Iterables.get(iterable, i))} returns {@code true},<a name="line.683"></a>
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<span class="sourceLineNo">700</span>   *<a name="line.700"></a>
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<span class="sourceLineNo">952</span>   * @throws IllegalArgumentException if {@code limitSize} is negative<a name="line.952"></a>
<span class="sourceLineNo">953</span>   * @since 3.0<a name="line.953"></a>
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<span class="sourceLineNo">969</span>   * {@link Iterator} through {@link Iterators#consumingIterator(Iterator)}.<a name="line.969"></a>
<span class="sourceLineNo">970</span>   *<a name="line.970"></a>
<span class="sourceLineNo">971</span>   * &lt;p&gt;Note: If {@code iterable} is a {@link Queue}, the returned iterable will<a name="line.971"></a>
<span class="sourceLineNo">972</span>   * get entries from {@link Queue#remove()} since {@link Queue}'s iteration<a name="line.972"></a>
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<span class="sourceLineNo">974</span>   * iterator from the returned iterable may cause an item to be immediately<a name="line.974"></a>
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<span class="sourceLineNo">982</span>   *<a name="line.982"></a>
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<span class="sourceLineNo">1026</span>   *<a name="line.1026"></a>
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<span class="sourceLineNo">1029</span>   * (which one does using {@link Iterator#hasNext}).<a name="line.1029"></a>
<span class="sourceLineNo">1030</span>   *<a name="line.1030"></a>
<span class="sourceLineNo">1031</span>   * @return {@code true} if the iterable contains no elements<a name="line.1031"></a>
<span class="sourceLineNo">1032</span>   */<a name="line.1032"></a>
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<span class="sourceLineNo">1040</span>  /**<a name="line.1040"></a>
<span class="sourceLineNo">1041</span>   * Returns an iterable over the merged contents of all given<a name="line.1041"></a>
<span class="sourceLineNo">1042</span>   * {@code iterables}. Equivalent entries will not be de-duplicated.<a name="line.1042"></a>
<span class="sourceLineNo">1043</span>   *<a name="line.1043"></a>
<span class="sourceLineNo">1044</span>   * &lt;p&gt;Callers must ensure that the source {@code iterables} are in<a name="line.1044"></a>
<span class="sourceLineNo">1045</span>   * non-descending order as this method does not sort its input.<a name="line.1045"></a>
<span class="sourceLineNo">1046</span>   *<a name="line.1046"></a>
<span class="sourceLineNo">1047</span>   * &lt;p&gt;For any equivalent elements across all {@code iterables}, it is<a name="line.1047"></a>
<span class="sourceLineNo">1048</span>   * undefined which element is returned first.<a name="line.1048"></a>
<span class="sourceLineNo">1049</span>   *<a name="line.1049"></a>
<span class="sourceLineNo">1050</span>   * @since 11.0<a name="line.1050"></a>
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<span class="sourceLineNo">1058</span>    Iterable&lt;T&gt; iterable = new FluentIterable&lt;T&gt;() {<a name="line.1058"></a>
<span class="sourceLineNo">1059</span>      @Override<a name="line.1059"></a>
<span class="sourceLineNo">1060</span>      public Iterator&lt;T&gt; iterator() {<a name="line.1060"></a>
<span class="sourceLineNo">1061</span>        return Iterators.mergeSorted(<a name="line.1061"></a>
<span class="sourceLineNo">1062</span>            Iterables.transform(iterables, Iterables.&lt;T&gt;toIterator()),<a name="line.1062"></a>
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<span class="sourceLineNo">1068</span><a name="line.1068"></a>
<span class="sourceLineNo">1069</span>  // TODO(user): Is this the best place for this? Move to fluent functions?<a name="line.1069"></a>
<span class="sourceLineNo">1070</span>  // Useful as a public method?<a name="line.1070"></a>
<span class="sourceLineNo">1071</span>  private static &lt;T&gt; Function&lt;Iterable&lt;? extends T&gt;, Iterator&lt;? extends T&gt;&gt;<a name="line.1071"></a>
<span class="sourceLineNo">1072</span>      toIterator() {<a name="line.1072"></a>
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<span class="sourceLineNo">1075</span>      public Iterator&lt;? extends T&gt; apply(Iterable&lt;? extends T&gt; iterable) {<a name="line.1075"></a>
<span class="sourceLineNo">1076</span>        return iterable.iterator();<a name="line.1076"></a>
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<span class="sourceLineNo">1078</span>    };<a name="line.1078"></a>
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<span class="sourceLineNo">1080</span>}<a name="line.1080"></a>




























































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